#1318 WIM creator alternate streams and empty dirs bugs

open
nobody
None
5
2012-12-07
2012-09-22
maxpat78
No

The WIM creator in 7-zip 9.29a actually stores alternate streams content, but doesn't record the stream names in the DIRENTRY structures: so the alternate streams can't be restored by ImageX 6.1.
(Note that ImageX itself has the opposite bug: it stores the stream names, but not their contents...).

Also, when testing a bad WIM containing an empty folder's DIRENTRY with liSubdirOffset member set to NULL instead of pointing to the following end-of-directory 64-bit marker, 7-zip doesn't detect such an error (while ImageX does).

Discussion

  • Igor Pavlov

    Igor Pavlov - 2012-09-23

    1) please write more details.
    Create smallest examples with ImageX and 7-Zip.
    And describe the difference

    2) As I remember there are some WIM files (maybe old WIM files),
    that used empty liSubdirOffset. Maybe it was in case of empty WIM file.

     
  • maxpat78

    maxpat78 - 2012-09-23

    1) I'm sorry, 7-zip can't capture alternate streams at all (the false impression depended on an abandoned link in my src dir...): in fact, there's no difference. But a problem remains: ImageX saves the alternate stream names, but not their content, how it is expected to do. See details in the DOCX.

    2) I can't reproduce the problem. Today, all WIM I can create with 7-zip and ImageX have a .liSubdirOffset not empty; and, after it has been set to zero by hand, both apps correctly refuse to open it as a WIM archive. But a few days ago, I had a buggy WIM with NULL liSubdirOffset (made with a script of mine) that 7-zip opened (but couldn't extract), while ImageX even refused to /DIR.

     
  • Igor Pavlov

    Igor Pavlov - 2012-09-23

    I have no docx reader. Please use plain txt.

     
  • maxpat78

    maxpat78 - 2012-09-23
     
  • maxpat78

    maxpat78 - 2012-09-23

    PDF? There's a commented hexdump inside, can't be rendered otherwise.

     
  • Igor Pavlov

    Igor Pavlov - 2012-09-23

    7-Zip now doesn't support links and repase tags.
    I have some plans to look it more later.

    Do you see any other problems with cases without links?

     
  • maxpat78

    maxpat78 - 2012-09-23

    Not actually, but I'll tell you. I'm writing a WIM creator with a Python script and using ImageX and 7-zip as reference/test tools.

     

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